Regenerative medicine strives to replace damaged cells, tissues or organs. Those that seek its restorative power may suffer from disease or congenital defects, injury or simply the effects of ageing. Recently, the use of animals in regenerative treatment techniques has gained popularity, particularly in regards to the growth of human organs within animal bodies. Currently, in popular cell-based therapies prominent in regenerative medicine, transplanted cells gather nutrients from blood vessels present at the graft site. However, transplanted cells may have a harder time thriving on organs and tissues with more significant injuries, which need a boost to promote wound healing so that they may sustain transplanted cells. In order to help cells grow more effectively and encourage the reconstruction of tissues, Dr Jun Negishi and his colleagues with the research laboratories at Shinshu university are making use of decellularized tissues. Negishi's goals include using decellularized tissue to promote growth of transplanted cells post engraftment by stimulating wound healing, aiding with tissue and organ regeneration and using animal tissues to develop optimal decellularized tissue. The latter builds on the latest technologies allowing human organs to be generated within animal bodies.